In the manufacture of in-line six cylinder internal combustion engines, cores have been lifted manually from delivery hooks by a rotating crew of three people, two of which must walk back and forth from the delivery rail system to an assembly fixture. In the assembly of the cores, two people, one person at each end of a core, standing on opposite sites of a horizontal fixture, must reach out beyond their center of gravity to place each core, which weighs approximately 55–64 lbs., into a core assembly fixture. The assembled cores, as a unit, are then mechanically raised out of the core assembly fixture and manually rolled on a horizontal track conveyor to a second station where the cores are bolted together by two additional people. The bolted core assemblies are then lowered onto storage boards on a horizontal conveyor and manually rolled out of the assembly area onto a storage elevator.
More specifically, in a typical core assembly operation for the assembly of cores for the manufacturing of in-line six cylinder internal combustion engines, cores are taken from an overhead conveyor that carries the cores in an L-shaped path adjacent a large horizontal table on which the cores are assembled. One man stationed at the side of the long horizontal table that is not adjacent the conveyor line takes tappet cores off a conveyor line and places them into a core assembly fixture. Two men place the barrels for formation of the engine cylinders into the fixture in numerical order. The second man working in this core assembly area takes the barrels for cylinders one, three and five off an overhead conveyor and places them into the core assembly fixture. The third man working in this area takes the barrels for cylinders two, four and six off the overhead conveyor and places them in the core assembly fixture. The barrels must be accurately seated on the locating surfaces of the core assembly fixture, and since each barrel weighs about 55–64 lbs., the first man helps the second and third men lower their barrels into the fixture and lowers the head face into the fixture while the second and third men lower the pan rails into the fixture. The first man then books the barrels and raises the tappet, and the second and third men place end cores into the fixture and close the end cores on the assembly. The three men then return to the assembly of the next core assembly. Two additional men pull the assembled core package to the opposite end of the horizontal assembly table, place a bottom board under the assembled core package, and insert threaded rods to hold the assembled core package together, one man holding the rods while the second man places washers and nuts on the threaded rod and tightens the nuts to hold the core together. These latter two men then lower the assembled and fastened core package onto a storage board, push the transfer carriage back to the other end of the assembly table and push the assembled and fastened core package onto a conveyor means for transfer to storage.
Thus, there is a need for a more accurate and ergonomically acceptable process and apparatus to assemble the core components of an internal combustion engine, and particularly the nine individual components that make up a core package used in the manufacture of an in-line cylinder engine, which weighs about 425 lbs. when assembled.